From what I see on the screenshot your DoD is a Steam version. If you claim it is no-steam that means it is illegal cracked version. Metamod, Sandbot and every official mod I know do not try to support any kind of cracked releases, because it's illegal and we don't want to get in trouble with authorities.

The thing you can do is to buy and install the official version of DoD, test again and then report if you have any troubles.

Thanks for your advice Storm, but I never thought if cracked version would causing a problem like this. Of course this error was happened to me for the first time since I have a lot of cracked Half Life Mods that could be played with Sandbot without any trouble (like Opposing Force, Natural Selection, etc)

Also you are trying to use Metamod-P-38 on Op4 Linux then you best of using P-37. I've had that "140" error from P-38 appear to be having problems with Op4, CS 1.6 and CZero from where I've encountered those problems on my Linux server.